Which Muscle is Botox Injected into Correct Slightly Lopsided Smile? I had a midface procedure that has given me some nerve injury, its been almost 3 weeks, I can smile wide and force movement but if I smile naturally my lips cover my teeth more on the right side, would it be the levator labii superioris alaeque nasi that is injected with a few units of botox to regain symmetry on the other side? Can this give the look of a more prominant nasalabial fold? or would it be another area on the cheek that effects lifting the corner of the lip that should be weakened.

Botox for smile asymmetry is risky business. I think you are thinking along the right lines anatomically, injecting the 'uninjured' side to weaken your lip elevators (LLSAN and other muscles) innervated by the buccal branch of facial nerve would probably work - but may result in a new type of asymmetry. I personally would wait this one out - most facial nerve injuries recovery spontaneously and you should have full lip elevator function back in a few months. We offer cosmetic Botox treatments in our Seattle clinic to rejuvenate the face, soften line and wrinkles.